提高电能质量的风柴蓄独立微电网分层协调控制

Hierarchical Coordinated Control of Islanded Wind-Diesel-Battery Microgrid for Improving Power Quality

针对高渗透率间歇性能源和频繁投切的系统负荷对独立微电网运行控制的影响,在充分考虑柴油发电机和电池储能不同控制特性的基础上,提出一种基于不同时间尺度的独立微电网分层协调控制方案,分别设计了基于蓄电池储能的一级控制器和基于柴油发电机的二级控制器来提高系统电压、频率在不同时间尺度上的稳定性.针对较短时间尺度及较小变化幅度的随机净负荷波动,通过改进蓄电池储能系统的P-f和Q-V下垂控制器来提高系统电压、频率的稳定性;而对于变化周期长和变化幅度大的净负荷波动,分别采用比例积分控制器和辅助无功补偿器来实现柴油发电机组对系统频率和电压的无差控制,从而保证系统稳定性.最后,通过对东澳岛风柴蓄独立微电网在不同运行条件下的运行控制结果分析,验证了所提方法的可行性和有效性.

As the high-penetration intermittent microsource and the frequently-switched load may impact the opera- tion stability of islanded microgrids, a hierarchical coordinated control scheme based on different time scales, which takes into full consideration the control characteristics of both the diesel generator and the battery storage system, is proposed. In this scheme, a primary controller based on the battery storage system and a secondary controller based on the diesel generator are designed to improve the stability of voltage and frequency of islanded microgrids in diffe- rent time scales. Moreover, in order to resist smaller and faster random system net-load disturbances, a modified droop controller with P-f and Q-V controls of the battery storage system is proposed, which helps to improve the sta- bility of system voltage and frequency. At the same time, in order to resist bigger and slower system net-load dis- turbances, a PI controller and an auxiliary reactive power compensator are presented for the diesel generator, which helps to implement the isochronous control of system frequency and voltage and to further restore the system operation stability. The feasibility and effectiveness of the proposed method is finally verified bv the analvsis of Done＇ ao islanded wind-diesel-battery microgrid operated in various conditions.